1. Field of the Invention
The present invention is generally directed toward acoustic energy dampening nozzles, and hazard-suppression systems employing those nozzles, which reduce the intensity of sound waves generated during passage of a gas therethrough. Particularly, nozzles according to the present invention comprise a series of internal partitions that define a flow path for the gas as it passes through the nozzle. The flow path is configured so as to expand the gas thereby reducing its velocity as it traverses between the nozzle inlet and outlet.
2. Description of the Prior Art
Hazard-suppression systems, especially fire-suppression systems, are widely employed to protect enclosed spaces housing valuable equipment, such as computer servers, from damage due to a fire. Certain hazard-suppression systems useful in this regard involve the introduction of an inert gas, such as nitrogen, argon, or a mixture thereof, into the area being protected. The introduction of an inert gas into the enclosed space reduces the oxygen concentration in the space to a level that is too low to support combustion. However, enough breathable oxygen remains within the enclosed space to allow for the safety of persons within the space at the time the suppression system is activated.
However, preventing damage from fire and heat is not the only concern for hazard-suppression systems designed to protect computer server rooms. The article “Fire Suppression Suppresses WestHost for Days,” Availability Digest, May 2010, describes the damage that can be done to computer hard disk drives during activation of an inert gas hazard-suppression system. While performing a test of the hazard-suppression system, an actuator fired which accidentally triggered the release of a large blast of inert gas into an area housing hundreds of servers and disk storage systems. During this accidental release, many of these servers and storage systems were severely damaged.
It was later discovered that the primary cause of damage to the hard disks was not the exposure to the fire-suppressing gas agent, but rather noise that accompanied the accidental triggering of the fire-suppression system. See, “Fire Suppressant's Impact on Hard Disks,” Availability Digest, February 2011. Subsequent testing also showed that loud noises, such as those generated by the activation of the fire-suppression system, can reduce the performance of hard disk drives by up to 50%, resulting in temporary disk malfunction and damage to disk sectors. Thus, the foregoing incident shed light on the problem of noise levels during activation of inert gas fire-suppression systems, and the need for controlling noise in order to adequately protect sensitive computer equipment.